The Browns are already dealing with another rebuild after changing coaching and front office staffs yet again. While roster changes understandably followed, losing a veteran center could have been a fatal blow to their plans.

Teams just don't replace a five-year starter at center with just anyone. Losing Mack would have meant a new captain of the offensive line, potentially a rookie. The entire Browns offense could have been set back a year or longer had they let him leave.

Mack, a five-year veteran, is a two-time Pro Bowler.Marco Garcia

But now the Browns have to factor in Mack's financial hit when deciding where else to spend their money. Will signing Mack to such a large contract now—which benefits them immediately—hurt them in the long term?

While five years and $42 million seems like a long time and a lot of money, the Browns aren't on the hook for every penny. Just $18 million of the contract is guaranteed, and that cash comes in the first two years of the contract—$10 million this year and $8 million for 2015.

After the first two years, Mack can opt out. If he stays, then only an additional $8 million is guaranteed to him, paid out for 2016. Each of his last two seasons on the contract are worth $8 million—a $6 million salary boosted by $2 million in roster bonuses. However, the Browns can choose not to pay those bonuses, and thus the rest of his contract, making Mack a free agent.

Breaking Down Alex Mack's Five-Year Deal

Year

Base

Roster Bonus

Cap Charge

Dead Money

2014

$10 million

$0

$10 million

$18 million

2015

$8 million

$0

$8 million

$8 million

2016

$8 million

$0

$8 million

$0

2017

$6 million

$2 million

$8 million

$0

2018

$6 million

$2 million

$8 million

$0

via OvertheCap.com. Mack can opt out after year 2, the Browns after year 3.

However, the Browns need to be financially ready for any possibility, ranging from Mack choosing free agency in 2016, the Browns letting him go in 2017 or keeping him for the duration of the deal. They could face the possibility of having to choose Mack over giving a contract to someone else, or vice versa.

Even with Mack's deal, Spotrac has the Browns' current cap space at over $30 million. They could certainly use some of that cash to pay other free agents, and of course, a few million of that will also be committed to this year's rookie class. However, they should be carrying over at least $20 million into 2015.

Currently, the Browns have just over $86 million in cap space accounted for in 2015. Should the salary cap rise significantly from the $133 million it was this year—and it is expected—the Browns could have as much as $75 million in cap space next year, if not more.

If the Browns had less cap space, then Joe Haden's status in 2015 would be in question. As it stands now, neither side needs to worry.Jason Miller/Getty Images

That's a lot of money, cash they can spend on high-priority free agents like cornerback Joe Haden, tight end Jordan Cameron, defensive tackle Phil Taylor and, depending on what happens this year, quarterback Brian Hoyer. They can sign all four to lucrative deals and still not break the bank.

They should still be in good financial standing in 2016, when wide receiver Josh Gordon becomes an unrestricted free agent. And, even if they start feeling the strain of their more lucrative contracts, as of now just Gordon is a must-re-sign for 2016. And there's always the possibility that Mack backs out of his contract, giving the Browns an $8 million cap savings.

It's clear that the Browns didn't break the bank for Mack. At face value, it certainly is a lot of money to pay for a center, even if they only end up being on the hook for $18 million for the first two years. But, even if they pay out the maximum value, it won't come at the expense of any other needed player on the roster.

Had the Browns been just $12 million under the cap when the Jaguars gave Mack the offer sheet, then this deal might spell trouble for their 2015 and 2016 free agents. Either that, or they would have had to pass on matching the contract and found their starting center elsewhere.

Blockbuster contracts like Mack's can often be a team's undoing. However, the Browns' liberal amount of salary cap space—a trend that should continue even while Mack is under contract—made matching the Jaguars' offer relatively painless. The fact that Mack can walk away in 2016 and the Browns can ditch the contract themselves in 2017 with no cap repercussions is just icing on the cake.